Is it possibl;e to run a program out of My Passport rather than off the hard drive

I am not necessarly computer illiterate but am unsure if this would be possible.  Ideally i would like to run iTunes or Fireworks off of an external narhdrive freeing up space on my laptop.  I just got the WD My Passport Essential 500GB.  Any answers or a direction to answers would be great.

Yes you sure can! Your passport acts like a drive just like your internal drive in your computer. BUT the only thing is that the program files will now be ran under your portable drive. Meaning, everytime you want to use that program YOU MUST have the passport with you. Also, the passport will have a higher rate of failure than your internal drive. 

You can. Is it recommended? No.